From mboxrd@z Thu Jan 1 00:00:00 1970 From: "shesha Sreenivasamurthy (shesha)" Subject: Re: Unlinking hugepage backing file after initialiation Date: Wed, 30 Sep 2015 22:04:36 +0000 Message-ID: References: <20150929161628.GA3810@redhat.com> <20150930003531-mutt-send-email-mst@redhat.com> <2601191342CEEE43887BDE71AB97725836AA21E7@irsmsx105.ger.corp.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Cc: "Michael S. Tsirkin" To: "Ananyev, Konstantin" , "dev@dpdk.org" Return-path: Received: from rcdn-iport-9.cisco.com (rcdn-iport-9.cisco.com [173.37.86.80]) by dpdk.org (Postfix) with ESMTP id 591718DAB for ; Thu, 1 Oct 2015 00:04:39 +0200 (CEST) In-Reply-To: <2601191342CEEE43887BDE71AB97725836AA21E7@irsmsx105.ger.corp.intel.com> Content-Language: en-US List-Id: patches and discussions about DPDK List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Sender: "dev" My bad that I said its not working, apologies. Isn=92t it correct to say that single process application do not benefit fr= om having backing files ? In that case can make this configurable by passin= g a command line argument that will either unlink or keep the backing files= , defaulting it to keeping the backing files. Single process application to= do not need these files around can pass additional param to unlink these f= iles ? -- - Thanks char * (*shesha) (uint64_t cache, uint8_t F00D) { return 0x0000C0DE; } From: "Ananyev, Konstantin" > Date: Wednesday, September 30, 2015 at 2:53 PM To: Cisco Employee >, "dev@dpdk.o= rg" > Cc: "Michael S. Tsirkin" > Subject: RE: [dpdk-dev] Unlinking hugepage backing file after initialiation -----Original Message----- From: dev [mailto:dev-bounces@dpdk.org] On Behalf Of shesha Sreenivasamurth= y (shesha) Sent: Wednesday, September 30, 2015 10:44 PM To: dev@dpdk.org Cc: Michael S. Tsirkin Subject: Re: [dpdk-dev] Unlinking hugepage backing file after initialiation What I heard is the following: A multi-process DPDK application, working ei= ther in master-worker or master-slave fashion, can potentially benefit by keeping the backing files in hugetlbfs. However, it = is does not work today as the pages are cleaned and added back when the application restarts. Who says it is not working? I admit that DPDK MP model is probably a bit constrained, but it does work. It is probably good to read some docs: http://dpdk.org/doc/guides/prog_guide/multi_proc_support.html and/or look at the code that does MP support inside DPDK. I think that might make things clearer. Konstantin On the other hand, for a single process application there is actually no be= nefit keeping the pages around. Therefore, I was wondering if we can make this configurable by passing a co= mmand line argument that will either unlink or keep the backing files. -- - Thanks char * (*shesha) (uint64_t cache, uint8_t F00D) { return 0x0000C0DE; } From: "Michael S. Tsirkin" > Date: Tuesday, September 29, 2015 at 2:35 PM To: Cisco Employee > Cc: "Xie, Huawei" >, "dev@dpdk.org" > Subject: Re: [dpdk-dev] Unlinking hugepage backing file after initialiation On Tue, Sep 29, 2015 at 05:50:00PM +0000, shesha Sreenivasamurthy (shesha) = wrote: Sure. Then, is there any real reason why the backing files should not be unlinked ? AFAIK qemu unlinks them already. -- MST